A federal appeals court dismissed New York City’s blanket lawsuit against the gun industry on Wednesday, ruling that a relatively new federal law protects gunmakers against third-party litigation.

The appellate ruling killed off — once and for all, perhaps — legal efforts by the city to charge gunmakers and distributors with knowingly flooding illicit, underground markets with their weapons. ....

In December 2005, Judge Jack B. Weinstein, of United States District Court in Brooklyn, allowed the suit to move forward despite protests by gunmakers like Beretta U.S.A., Browning Arms, Colt Manufacturing, Glock and Smith & Wesson, which pointed to a federal law passed two months earlier in October. That law, the Protection of Lawful Commerce in Arms Act, banned all third-party suits against the gun industry except for those in which a plaintiff could prove that gunmakers had violated other state or federal statutes in their sales and marketing practices.

Mayor Michael R. Bloomberg’s administration argued that the gun manufacturers, by failing to monitor retail dealers closely enough, allowed guns to end up in the hands of criminals. As a result, the manufacturers created a “condition that negatively affects the public health or safety,” the city said and, thus, violated New York State’s public nuisance law.

The Second Circuit held that the New York's nuisance statute did not constitute a permissible exception under the federal Protection of Lawful Commerce in Arms Act. The court therefore reversed Judge Weinstein's denial of the defendants' motion to dismiss. Judge Katzmann, dissenting, would have certified to the New York Court of Appeals the question of whether New York's nuisance statute is applicable to the sale and marketing of firearms.